Deep beneath the frozen Arctic are deposits of methane. Lots of methane. And there's even more on the sea floor. As the environment warms, these deposits are being released into the atmosphere, presenting grave risks of runaway warming.

For today's Geo Quiz, we head to the frozen north. We have heard a lot about the problem of melting ice as climate change warms up the Arctic. But scientists are also worried about something else that is melting up there &mdash; permafrost.

For today's Geo Quiz, we head to the frozen north. We have heard a lot about the problem of melting ice as climate change warms up the Arctic. But scientists are also worried about something else that is melting up there &mdash; permafrost.

Deep beneath the frozen Arctic are deposits of methane. Lots of methane. And there's even more on the sea floor. As the environment warms, these deposits are being released into the atmosphere, presenting grave risks of runaway warming.

Deep beneath the frozen Arctic are deposits of methane. Lots of methane. And there's even more on the sea floor. As the environment warms, these deposits are being released into the atmosphere, presenting grave risks of runaway warming.

For today's Geo Quiz, we head to the frozen north. We have heard a lot about the problem of melting ice as climate change warms up the Arctic. But scientists are also worried about something else that is melting up there &mdash; permafrost.

Deep beneath the frozen Arctic are deposits of methane. Lots of methane. And there's even more on the sea floor. As the environment warms, these deposits are being released into the atmosphere, presenting grave risks of runaway warming.